1. Field of the Invention
The invention relates to image processing and, more particularly, relates to techniques for automatically generating a site model from images of a site.
2. Description of the Related Art
The mainstay of geographical information systems is the depiction of land occupied by buildings using a two-dimensional map. Increasingly, there is a need for three-dimensional (3D) representations of buildings to augment the geographical information. Such 3D information may be required in architectural design application and wireless infrastructure planning applications. Ideally, geographical information should contain a database encompassing extensive areas of land (e.g., suburban residential areas) while containing details about the shape and texture of each building from all vantage points.
Using commercially available software, the process of extracting information for creating such a database is labor-intensive. Typically, the process uses a series of aerial images recorded viewing a scene from above, e.g., a plurality of aerial photographs of a neighborhood. Typical aerial photographs lack sufficient information for complete 3D modeling of a building's shape and appearance. However, the aerial photographs can be augmented with information from a plurality of high-resolution, oblique photographs of the scene (site). A manual process is currently used to outline buildings in the aerial photographs and then identify oblique information that corresponds to the building outlines. The oblique information (e.g., a building's shape and texture, is manually aligned with the outlines to prepare a 3D view of the building(s). Because the process is so time consuming, the process is generally used for only a select number of buildings.
Therefore, there is a need in the art for techniques for generating 3D site models using automated processes to provide more comprehensive site models.